Defining remission in childhood-onset lupus: PReS-endorsed consensus definitions by an international task force

OBJECTIVE

To derive childhood-onset SLE (cSLE) specific remission definitions for future treat-to-target (T2T) trials, observational studies, and clinical practice.

METHODS

The cSLE International T2T Task Force conducted Delphi surveys exploring paediatric perspectives on adult-onset SLE remission targets. A modified nominal group technique was used to discuss, refine, and agree on the cSLE remission target criteria.

RESULTS

The Task Force proposed two definitions of remission: 'cSLE clinical remission on steroids (cCR)' and 'cSLE clinical remission off steroids (cCR-0)'. The common criteria are: (1) Clinical-SLEDAI-2 K = 0; (2) PGA score < 0.5 (0-3 scale); (4) stable antimalarials, immunosuppressive, and biologic therapy (changes due to side-effects, adherence, weight, or when building up to target dose allowed). Criterion (3) in cCR is the prednisolone dose ≤0.1 mg/kg/day (maximum 5 mg/day), whereas in cCR-0 it is zero.

CONCLUSIONS

cSLE definitions of remission have been proposed, maintaining sufficient alignment with the adult-SLE definition to facilitate life-course research.

Glomerulonephritis

Glomerulonephritis (GN) encompasses several disorders that cause glomerular inflammation and injury through an interplay of immune-mediated mechanisms, host characteristics, and environmental triggers, such as infections. GN can manifest solely in the kidney or in the setting of a systemic illness, and presentation can range from chronic and relatively asymptomatic hematuria to fulminant renal failure. Classic acute GN is characterized by hematuria, edema, and hypertension, the latter 2 of which are the consequence of sodium and water retention in the setting of renal impairment. Although presenting signs and symptoms and a compatible clinical history can suggest GN, serologic and urinary testing can further refine the differential diagnosis, and renal biopsy can be used for definitive diagnosis. Treatment of GN can include supportive care, renin-angiotensin-aldosterone system blockade, immunomodulatory therapy, and renal transplant. Prognosis is largely dependent on the underlying cause of GN and can vary from a self-limited course to chronic kidney disease. This review focuses on lupus nephritis, IgA nephropathy, IgA vasculitis, and postinfectious GN.

Management and outcomes in children with lupus nephritis in the developing countries

BACKGROUND

Lupus nephritis (LN) has variable prevalence, severity, and outcomes across the world.

OBJECTIVES

This review compares the outcomes of childhood LN in low- and middle-income countries (LMICs) and high-income countries (HICs) and aims to summarize long-term outcomes of pediatric LN from LMICs.

DATA SOURCES

A systematic literature search, conducted in PubMed, EMBASE, and Cochrane database in the last 30-years from January 1992, published in the English language, identified 113 studies including 52 from lower (n = 1336) and upper MICs (n = 3014).

STUDY ELIGIBILITY CRITERIA

Cohort studies or randomized controlled trials, of patients ≤ 18 years of age (or where such data can be separately extracted), with > 10 patients with clinically or histologically diagnosed LN and outcomes reported beyond 12 months were included.

PARTICIPANTS AND INTERVENTIONS

Patients ≤ 18 years of age with clinically or histologically diagnosed LN; effect of an intervention was not measured.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two authors independently extracted data. We separately analyzed studies from developed countries (high income countries; HIC) and developing countries (LMICs). Middle-income countries were further classified as lower and upper MICs. Meta-analyses of data were performed by calculating a pooled estimate utilizing the random-effects model. Test for heterogeneity was applied using I² statistics. Publication bias was assessed using funnel plots.

RESULTS

Kidney remission was similar across MICs and HICs with 1-year pooled complete remission rates of 59% (95% CI 51-67%); one third of patients had kidney flares. The pooled 5-year survival free of stage 5 chronic kidney disease (CKD5) was lower in MICs, especially in lower MICs compared to HICs (83% vs. 93%; P = 0.002). The pooled 5-year patient survival was significantly lower in MICs than HICs (85% vs. 94%; P < 0.001). In patients with class IV LN, the 5-and 10-year respective risk of CKD5 was 14% and 30% in MICs; corresponding risks in HICs were 8% and 17%. Long-term data from developing countries was limited. Sepsis (48.8%), kidney failure (14%), lupus activity (18.1%), and intracranial hemorrhage/infarct (5.4%) were chief causes of death; mortality due to complications of kidney failure was more common in lower MICs (25.6%) than HICs (6.4%).

LIMITATIONS

The review is limited by heterogenous approach to diagnosis and management that has changed over the period spanning the review. World Bank classification based on income might not correlate with the standards of medical care. The overall quality of evidence is low since included studies were chiefly retrospective and single center.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Challenges in LMICs include limited access to pediatric nephrology care, dialysis, increased risk of infection-induced mortality, lack of frequent monitoring, and non-compliance due to cost of therapy. Attention to these issues might update the existing data and improve patient follow-up and outcomes.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO 2022 number: CRD42022359002, available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022359002.

Risk factors for subsequent lupus nephritis in patients with juvenile-onset systemic lupus erythematosus: a retrospective cohort study

BACKGROUND

Lupus nephritis (LN) is a crucial organ involvement in systemic lupus erythematosus (SLE). Patients with LN have higher morbidity and mortality rates than those without. Among all patients with LN, 20-40% had delayed onset, but the data for patients with juvenile-onset SLE (jSLE), who have a higher percentage of LN than patients with adult-onset SLE (aSLE), were limited. This study aimed to determine the risk factors for subsequent LN in patients with jSLE.

METHODS

A retrospective cohort study was conducted between 2008 and 2018 in a single tertiary medical centre. Patients with diagnosed jSLE were reviewed. We investigated those without LN at diagnosis and whether they developed LN afterward. The primary outcome was the development of subsequent LN. Clinical manifestations at diagnosis, serial laboratory data, and treatments were reviewed during follow-up periods.

RESULTS

Among the 48 patients with jSLE without initial LN, 20 developed subsequent LN later (Group 1), whereas 28 remained free of LN (Group 2). There was no difference in the percentage of initial manifestations except for more discoid rashes in Group 2 patients. In the Cox regression model, elevated average anti-double-stranded DNA (dsDNA) antibody, low average serum complements, and high average erythrocyte sedimentation rate (ESR) levels during follow-up were predictors of subsequent LN. After adjusting for these factors in multivariable analyses, only high average anti-dsDNA antibody and high average ESR levels remained predictive of subsequent LN. For every 100 IU/ml increase in anti-dsDNA antibody, the risk for subsequent LN in jSLE increases by 1.29 times (hazard ratio = 1.29, 95% confidence interval 1.055-1.573).

CONCLUSION

Persistently high anti-dsDNA antibody and ESR levels during the follow-up period were risk factors for subsequent LN in patients with jSLE.

Working Towards a Treat-to-Target Protocol in Juvenile Proliferative Lupus Nephritis - A Survey of Pediatric Rheumatologists and Nephrologists in Germany and Austria

BACKGROUND

To describe treatment practices for juvenile proliferative lupus nephritis (LN) class III and IV of pediatric rheumatologists and nephrologists in Germany and Austria in preparation for a treat-to-target treatment protocol in LN.

METHODS

Survey study by members of the Society for Pediatric and Adolescent Rheumatology (GKJR) and the German Society for Pediatric Nephrology (GPN) on diagnostics and (concomitant) therapy of LN.

RESULTS

Fifty-eight physicians completed the survey. Overall, there was a considerable heterogeneity regarding the suggested diagnostics and management of juvenile proliferative LN. Increased urinary protein excretion, either assessed by 24 h urine collection or spot urine (protein-creatinine ratio), and reduced estimated glomerular filtration rate were specified as important parameters for indication of kidney biopsy to diagnose proliferative LN and monitoring of therapy. Corticosteroids were generally proposed for induction and maintenance therapy, most often in conjunction with either mycophenolate mofetil (MMF) or cyclophosphamide (CP) as steroid-sparing immunosuppressants. MMF was clearly preferred over CP for induction therapy of LN class III, whereas CP and MMF were equally proposed for LN class IV. MMF was most often recommended for maintenance therapy in conjunction with oral corticosteroids and continued for at least 3 years and 1 year, respectively, after remission. Hydroxychloroquine was widely accepted as a concomitant measure followed by renin-angiotensin system inhibitors in cases of arterial hypertension and/or proteinuria.

CONCLUSION

The majority of pediatric rheumatologists and nephrologists in Germany and Austria propose the use of corticosteroids, most often in combination with either MMF or CP, for treatment of proliferative LN in children. The considerable heterogeneity of responses supports the need for a treat-to-target protocol for juvenile proliferative LN between pediatric rheumatologists and nephrologists.

Retrospective analysis of clinical and pathomorphological features of lupus nephritis in children

PURPOSE

The aim of the study was to evaluate the clinical course and pathomorphological correlations in Polish children with the diagnosis of lupus nephritis (LN).

METHODS

We retrospectively analyzed the medical records of 39 children hospitalized due to LN in 7 pediatric nephrology units in Poland between 2010 and 2019. Demographic data, clinical symptoms at the onset of LN and laboratory parameters were reviewed. We analyzed Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), histological LN findings with the activity (IA) and chronicity index (IC).

RESULTS

We examined 32 girls and 7 boys, median age at LN onset was 14.75 (IQR 13.0-16.0) years, SLEDAI of 22.0 (IQR 18.0-27.0) points; LN histological class: IV (59.4%), III (18.9%), III/V (10.8%), IV/V (8.1%), VI (2.7%); IA 8.0 (IQR 6.0-11.0) points, IC 1.05 (IQR 0-2.0) points. Children with nephrotic (n ​= ​22) and non-nephrotic (n ​= ​17) proteinuria differed in median Hb level (9.55, IQR 8.3-11.2 vs 10.9, IQR 10.1-11.6 ​g/L; P ​< ​0.05), albumin level (2.5, IQR 2.1-3.19 vs 3.6, IQR 3.4-4.1 ​g/dL; P ​< ​0.001), proteinuria (5.76, IQR 3.0-7.5 vs 1.08, IQR 0.53-1.50 ​g/day; P ​< ​0.0001), eGFR (53.9, IQR 27.0-68.8 vs 96.7, IQR 73.8-106.2 ​mL/min/1.73 ​m²; P ​< ​0.01) and occurrence of hypertension (77% vs 23%; P ​< ​0.01). In multivariate analysis Hb level (β ​= ​8.0; 95%CI, 1.90-14.11) was the significant predictor of eGFR<90 ​mL/min/1.73 ​m².

CONCLUSIONS

Proliferative forms of LN in children may have a varying clinical presentation. Children with LN with nephrotic range proteinuria have lower Hb level, lower eGFR and higher occurrence of hypertension. Hb level is the significant predictor of eGFR<90 ​mL/min/1.73 ​m² in children with LN.

Disparities in Childhood-Onset Lupus

Disparities in prevalence, disease severity, physical and mental morbidity, and mortality exist in childhood-onset systemic lupus (cSLE) that lead to worse outcomes in children with systemic lupus erythematosus from socially disadvantaged backgrounds. Important gaps exist in knowledge regarding many individual race/ethnicities across the globe, the interaction between race/ethnicity and poverty, and drivers for identified disparities. Large cSLE registries will facilitate investigating disparities in groups of patients that have yet to be identified. Social-ecological models can inform approaches to investigate, monitor, and address disparities in cSLE.

Influence of air pollution on renal activity in patients with childhood-onset systemic lupus erythematosus

BACKGROUND

Childhood-onset systemic lupus erythematosus (cSLE) is an autoimmune and multifactorial disease that can affect the renal system. Exposure to air pollution can trigger systemic inflammation in cSLE patients and increase risk of disease activity. We evaluated effects of individual real-time exposure to air pollutants on renal activity in cSLE patients using the Systemic Lupus Erythematosus Disease Activity Index 2000.

METHODS

Longitudinal panel study of 108 repetitive measures from 9 pediatric lupus patients. Over three consecutive weeks, daily individual levels of fine particulate matter (PM_2.5) and nitrogen dioxide (NO₂) were measured, as well as weekly clinical evaluation and laboratory tests. This was repeated every 10 weeks over a 1-year period. Specific generalized estimating equation models were used to evaluate the impact of these pollutants on risk of nephritis and anti-dsDNA > 20 UI/mL and on 24-h urine protein and serum complement (C3) levels.

RESULTS

An interquartile range (IQR) increase of 18.12 μg/m³ in PM_2.5 daily concentration was associated with increased risk of nephritis and positive results for anti-dsDNA. Moreover, increase in 24-h urine protein and decrease in C3 serum levels also associated with exposure to pollutants. An IQR increase in PM_2.57-day moving average was associated with increased risks of leukocyturia (3.4; 95% CI 2.6:4.3), positive anti-dsDNA (3.1; 95% CI 2.1:4.0), and 36.3-mg increase (95% IC 20.2:52.3) in 24-h urine protein. An IQR increase (63.1 μg/m³) in 7-day cumulative NO₂ levels was associated with decreased serum C3 levels.

CONCLUSIONS

This prospective study suggests exposure to air pollution can trigger renal activity in cSLE patients.

Comparison of lupus patients with early and late onset nephritis: a study in 71 patients from a single referral center

BACKGROUND

Nephritis occurs frequently in systemic lupus erythematosus (SLE) and may worsen disease morbidity and mortality. Knowing all characteristics of this manifestation helps to a prompt recognition and treatment.

AIM

To compare the differences in clinical data, serological profile and treatment response of nephritis of early and late onset.

METHODS

Retrospective study of 71 SLE patients with biopsy proven nephritis divided in early nephritis group (diagnosis of nephritis in the first 5 years of the disease) and late nephritis (diagnosis of nephritis after 5 years). Epidemiological, serological, clinical and treatment data were collected from charts and compared.

RESULTS

In this sample, 70. 4% had early onset nephritis and 29.6% had late onset. No differences were noted in epidemiological, clinical, serological profile, SLICC and SLEDAI, except that late onset nephritis patients were older at nephritis diagnosis (p = 0.01). Regarding renal biopsy classification, C3 and C4 levels, serum creatinine, 24 h proteinuria and response rate to treatment the two groups were similar (p = NS). Patients with early onset had lower levels of hemoglobin at nephritis onset than those of late onset (p = 0.02).

CONCLUSIONS

Most of SLE patients had nephritis in the first 5 years of disease. No major differences were noted when disease profile or treatment outcome of early and late onset nephritis were compared.